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Topic: Happy Birthday TRS-80 (Read 7793 times)

This amazing computer was one of the earliest affordable PCs that actually allowed small businesses to get serious work done. I installed a Model III in my sister's company back when dinosaurs (and me ) roamed the earth. With a 2Mhz Z80 chip, a whopping 48 kilobytes of RAM, dual 5" floppy drives, a butt-ugly silver/grey case, and a built-in and slightly fuzzy B&W TV screen (later replaced with a 'real' aftermarket amber CRT) for a monitor, it was a formidable beastie for its time. Other machines (including my beloved C=64) had panache and pretty graphics. My sister's had VisiCalc for spreadsheets, Electric Pencil for wordprocessing, a surprisingly complete and robust GL/AP/AR accounting package - and Zork for when nobody was looking. This all cost her about $2700 in 1981 - which would be roughly $9500 in today's dollars.

Anything else you may have needed got taken care of the way most things did back then - by you writing a program (in BASIC or Z80 assembly) to handle it. Radioshack had a particularly nice version of BASIC and a decent monitor for assembler. Which was a good thing. Because sooner or later, you'd end up using one (or both) of them.

For tech "support" you had your local "80" club, the nascent "Trash-80" BBS community (via Compuserve), and a fantastic magazine called 80 Microcomputing.

Although it may not sound like much today, back when big sister had this rig, she was one of the most "computerized" small businesses in her neck of the woods.

Nice article entitled Please Don’t Call It Trash-80: A 35th Anniversary Salute to Radio Shack’s TRS-80 can be found here.

Note: Check out this 80 Microcomputing cover from 1980. Seems like judicial sanity still prevailed back then - even though the editors might not have thought so. (How times have changed!)

It is the Model III. IIRC the Model I got yanked from distribution by the FCC because of excessive RF emissions. Radios supposedly used to make all kinds of weird noises if put too close to it.

The Model III was succeeded by the Model 4 (no more Roman numerals!) which was a real nice version. White case, better hardware (128Kb RAM + 4Mhz CPU, nicer 'real' monitor (80x24 vs the old 64x16), larger capacity floppy disks, etc. ) and could run CP/M or an alternative 3rd-party souped-up version of TRSDOS called LDOS. You could have used LDOS on the Model III too although it really came into its own with the faster CPU and higher capacity floppies on the Model 4.

Radioshack also did something called a Model II (and later the Tandy Model 12) (see below), which was their "big iron" offering .

It had two Shugart 8" floppy drives (expandable to 4) and ran CP/M or TRSDOS right out of the box. But you could also get add-ons (hard disk controller, graphics card) and a co-processor board with a Motorola 68000 chip and 512k of dedicated RAM which allowed you to run XENIX on it. That was a popular machine for midsize businesses looking for a relatively inexpensive system to run UNIX-based accounting and payroll apps. It was also popular with what used to be called "data-entry firms" because certain Model II/12 disks could be read by IBM and other minicomputers.

This machine was 'serious business' through and through and competed favorably against some of the lower end DEC and Commodore minicomputers from that era. Which just goes to show how far we've come since then. Especially when you consider any moderately technical hobbyist can assemble a supercomputer quite easily, and for far less money than my sister paid for her single-CPU TRS-80 desktop.

Loved that trapezoidal monitor casing it had. Hated the little chicklet-ty keyboard, although it had a nice professional adding machine touch to it. Definitely more geared towards data entry functions than touch typing. And at least the numeric entry pad was full sized. Looked something like a modern cash register. Saw one abandoned by the trash bins outside an old office building recently. I would have grabbed it except the monitor and insides had been smashed up. Quite recently too from the amount of glass all around it. Probably done by some passing kids who didn't realize what a collector's piece it was. *SIGH*

Used a DEC Rainbow too! That packed both a Z80 and an Intel 8080 chip in the same box. It could run CP/M 8 or 16, and also could be used as a straight data terminal too. I forget if it was VT-102 or just straight ANSI.

Commodore duped some of that design with their elegant C=128 which packed an 8502 plus a Z80 chip and allowed for three separate modes of operation: the traditional C=64, the jazzed-up C=128, and CP/M mode.

That damned cassette player!I still recall the pain of huddling all night over a TRS 80, producing the worst kind of spaghetti code in order to beat a deadline. Finally, as dawn broke and before sending it to cassette, I just had to stretch and in so doing inadvertently kicked the power plug out of its socket.Ouch!

That damned cassette player!I still recall the pain of huddling all night over a TRS 80, producing the worst kind of spaghetti code in order to beat a deadline. Finally, as dawn broke and before sending it to cassette, I just had to stretch and in so doing inadvertently kicked the power plug out of its socket.Ouch!

I had the same thing happen to me once with my C=64 and a 1530 Datasette drive. 4 hours of assembly programming using HesMON down the tubes! Went out and bought the 1541 Floppy Drive unit the following weekend.

Of course that drive had it's own problems if you too frequently loaded games off it. Electronic Arts and Origin games used deliberate bad sector/track tricks for copy protection. It used to cause the read/write heads to "slam" themselves dozens of times while loading Seven Cities of Gold, M.U.L.E. or Ultima III. You could actually feel it vibrate the tabletop sometimes. (It was usually four or five minutes of: Takka-takka-takka-takka *grind* whip-zip-zip-zip *grind* - and then... abrupt silence! It was scary.) All that head banging caused major alignment problems after a while.

Half-ass recalibrating these drives wasn't difficult if you had: a screwdriver and a few other tools, a special 'calibration' floppy disk, and the matching utility software. (A 'real' calibration required the above plus an oscilloscope so it was always good to have a friend or family member who was also a ham radio operator living nearby.) It was sort of a C=64 power user's rite of passage doing one of these. You had to crack the drive case (and void your warranty) to do it. But it was no harder than setting the dwell on a pre-fuel injection automobile engine. A little practice and a light steady touch were all that were needed. Most of us left the drive cases unscrewed and only elastic banded together after doing a few of those.

Recalibrating these drives wasn't difficult if you had: a screwdriver, a special 'calibration' floppy disk, and the matching utility software. It was sort of a C=64 power user's rite of passage doing one of these. You had to crack the drive case (and void your warranty) to do it. But it was no harder than setting the dwell on a pre-fuel injection automobile engine. A little practice and a light steady touch were all that were needed. Most of us left the drive cases unscrewed and only elastic banded together after doing a few of those.

I still have a Tandy TRS80 color in the attic. Working order, comes with a couple of program cartridges instead of floppy discs. Pretty sure the only one I have that I know works is Chess.

There's also a later model Tandy from the year 1991- it uses an Intel 386 SX CPU with most likely 2MB of RAM. Not sure what all is in it, I'd have to read the tags.It's still in it's factory packaging, and has never been booted. I got that while working at an old radioshack store cleaning out the back room, it was too old to sell so the guy said I could keep it.

There's also a later model Tandy from the year 1991- it uses an Intel 386 SX CPU with most likely 2MB of RAM. Not sure what all is in it, I'd have to read the tags.It's still in it's factory packaging, and has never been booted. I got that while working at an old radioshack store cleaning out the back room, it was too old to sell so the guy said I could keep it.

The 386SX is a yet another straight-up PC clone. Might be fun booting it up for old times sake. Especially if you have an old copy of Windows for Workgroups mothballed somewhere in there with it. A few hours with that will make almost anything that followed look and feel positively inspired - with the possible exception of Millenium Edition and Metro.